As an HR manager I would like to report on the burn rate of the Custom1 leave allowance so I can see how much training time my employees have used so far this year

I'd like to be able to pick which allowance to report on. We use Custom1 for an annual training allowance, and I'd really like to be able to see a report on how much training time people have used throughout the year so we can see whether we're expecting a flurry of training requests towards the end of the year (which may therefore be denied).